Queensland's Sunshine Coast is on measles alert after an adult was diagnosed with the highly infectious disease upon returning from southeast Asia.
Health authorities are still trying to trace people, including staff and patients at two Sunshine Coast hospitals, who might have come into contact with the infected adult.
Queensland Health says the unvaccinated adult likely acquired the virus during a recent trip to Vietnam.
Sunshine Coast Health Unit public health specialist Dr Andrew Langley says residents should be wary of unusual rashes and seek advice from their GP if in doubt.
A red, spotty rash and other measles symptoms, including a fever, cough and runny nose, usually appear 10 days after infection.
"Also, anyone intending to travel overseas should ensure they are up to date with their measles vaccination," Dr Langley said.